We extend the methods of Yennie, Frautschi, and Suura (YFS) to compute, via Monte Carlo methods, the effects of multiple gluon emission in the processes q+(q¯)’→q’’+(q¯)’’’+n(G), where G is a soft gluon. We show explicitly that the infrared singularities in the respective simulations are canceled to all orders in ${\mathrm{\alpha }}_{\mathit{s}}$. Some discussion of this result from the standpoint of confinement is given. More importantly, we present, for the first time, sample numerical Monte Carlo data on multiple soft gluon emission in the rigorously extended YFS framework. We find that such soft gluon effects must be taken into account for precise physics simulations at and beyond CERN LHC energies.

• Received 22 February 1994

DOI:https://doi.org/10.1103/PhysRevD.52.108